A safety device for a person in an underground duct, tunnel or the like, particularly for a person in a sewer pipe, is known in the form of a guide rail attached by spacers to the roof of the duct or tunnel, and a traveling body movable on and along the guide rail which is attached by a safety tether to a safety belt or harness worn by the person.
This safety device has been metnioned in the January 1985 issue of the periodical "Arbeit und Sicherheit" (Work and Safety), page 4. However it has not been constructed for practical usage.
A great need for such a safety device exists particularly in regard to sewer pipes, especially collector sewers.
It is frequently reported that a person has slipped on the smooth surface of a sewer pipe and has floated away in an unconscious state with the sewage. Help has usually arrived too late. Our invention provides a remedy for this problem.